Changeset f8143a6 for src/Common

Timestamp:

Feb 7, 2022, 12:50:05 PM (4 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, ast-experimental, enum, forall-pointer-decay, master, pthread-emulation, qualifiedEnum

Children:

250583e

Parents:

b56ad5e

Message:

Change pass visitor to avoid more transient strong references

File:

• src/Common/utility.h (modified) (1 diff)

src/Common/utility.h

@@ -371 +371 @@
 }
 
+template< typename T >
+struct enumerate_t {
+        template<typename val_t>
+        struct value_t {
+                val_t & val;
+                size_t idx;
+        };
+
+        template< typename iter_t, typename val_t >
+        struct iterator_t {
+                iter_t it;
+                size_t idx;
+
+                iterator_t( iter_t _it, size_t _idx ) : it(_it), idx(_idx) {}
+
+                value_t<val_t> operator*() const { return value_t<val_t>{ *it, idx }; }
+
+                bool operator==(const iterator_t & o) const { return o.it == it; }
+                bool operator!=(const iterator_t & o) const { return o.it != it; }
+
+                iterator_t & operator++() {
+                        it++;
+                        idx++;
+                        return *this;
+                }
+
+                using difference_type   = typename std::iterator_traits< iter_t >::difference_type;
+                using value_type        = value_t<val_t>;
+                using pointer           = value_t<val_t> *;
+                using reference         = value_t<val_t> &;
+                using iterator_category = std::forward_iterator_tag;
+        };
+
+        T & ref;
+
+        using iterator = iterator_t< typename T::iterator, typename T::value_type >;
+        using const_iterator = iterator_t< typename T::const_iterator, const typename T::value_type >;
+
+        iterator begin() { return iterator( ref.begin(), 0 ); }
+        iterator end()   { return iterator( ref.end(), ref.size() ); }
+
+        const_iterator begin() const { return const_iterator( ref.cbegin(), 0 ); }
+        const_iterator end()   const { return const_iterator( ref.cend(), ref.size() ); }
+
+        const_iterator cbegin() const { return const_iterator( ref.cbegin(), 0 ); }
+        const_iterator cend()   const { return const_iterator( ref.cend(), ref.size() ); }
+};
+
+template< typename T >
+enumerate_t<T> enumerate( T & ref ) {
+        return enumerate_t< T >{ ref };
+}
+
+template< typename T >
+const enumerate_t< const T > enumerate( const T & ref ) {
+        return enumerate_t< const T >{ ref };
+}
+
 template< typename OutType, typename Range, typename Functor >
 OutType map_range( const Range& range, Functor&& functor ) {